Question

How many milliliters of 0.755 m h2so4 solution is needed to react with 55.0 ml of 2.50 m koh solution? given: 2 koh (aq) + h2so4 (aq) → 2 h2o (l) + k2so4 (aq)?

Answer 1

KOH (2.50 mol/L) (0.0550 L) = 0.1375 mol

The KOH to H2SO4 molar ratio of 2 to 1 is the key. Only H2SO4 neutralized KOH

0.1375 mol / 2 = 0.06875 mol H2SO4 amount

volume required of H2SO4 ---> 0.06875 mol / 0.755 mol/L = 0.0910596 L = 91.0 mL

Answer 2

Answer:
moles KOH ---> (2.50 mol/L) (0.0550 L) = 0.1375 mol
The KOH to H2SO4 molar ratio of 2 to 1 is the key. Only half as much H2SO4 get neutralized compared to the KOH:
0.1375 mol / 2 = 0.06875 mol <--- that's the H2SO4 amount
volume required of H2SO4 ---> 0.06875 mol / 0.755 mol/L = 0.0910596 L = 91.0 mL (to three sig figs)